In multicast or broadcast applications, data are transmitted from a server to multiple receivers over wired and/or wireless networks. A multicast system is a system in which a server transmits the same data to multiple receivers simultaneously, where the receivers form a subset of all the receivers up to and including all of the receivers. A broadcast system is a system in which a server transmits the same data to all of the receivers simultaneously. That is, a multicast system by definition can include a broadcast system.
While the existing methods for delivering (transmitting, deploying) the left eye (LE)-right eye (RE) image difference as an additional layer achieve substantial stereoscopic compression, the bandwidth for the additional layer ranges from 30% to 60% of a single channel. This amount is still high and presents a problem for distribution, decoding, and storage.
An object is to find a practical and efficient method, which will deliver the additional layer in the image of 15% to 30% of the bandwidth of a single video stream.
The present compression method is better adapted to the stereoscopic 3D (S3D) structure of the LE and RE video image pair and exploits the intrinsic relation of the two picture channels. If the original S3D picture was captured using parallel camera rig or toe-in, or if it was captured (shot) applying creative scene depth, the two images in the pair have a deeper correlation, which could be extracted by non-linear rotation along the z-axis (or depth axis) of the images. The present invention uses this correlative feature, which comes from the particularities of the Human Visual System (HVS), and delivers better video transport compression.